Country faces strong possibility of hung parliament after voters fail to hand either of the top parties a majority.

Australia faces the prospect of a hung parliament, the second in six years, after neither of the country's major parties won enough seats to form a government in Saturday's general election.

With 77 percent of the votes counted on Sunday morning, the ruling Conservative coalition led by Prime Minister Malcolm Turnbull was neck-and-neck with the centre-left Labor Party, led by opposition leader Bill Shorten.

Each was projected to had secured about 67 seats, nine short of the majority needed in the 150-seat lower house.

Eleven seats were still too close to call. The Greens had won one, while four seats were taken by independent candidates.

A final outcome is not expected for days, as millions of postal and absentee votes have not yet been processed, with experts saying that these traditionally favour the incumbent.

Close race

A hung parliament remained a possibility, Attorney General George Brandis said.

Projections showed the most Turnbull could hope for was 74 seats, which would force him to cut a deal with independents and minor parties to stay in power.

Despite losing a host of coalition MPs, Turnbull, whose coalition won 90 seats in the 2013 election, sounded a confident tone during a speech to supporters early on Sunday morning.

"Based on the advice I have from the party officials, we can have every confidence that we will form a coalition majority government," the 61-year-old said, conceding, however, that the race was "very, very close".

Labor's Shorten told supporters that Turnbull's government had lost a clear mandate to govern.

"One thing is for sure, the Labor party is back," he said, but did not claim to have enough votes to form a government.

Political turmoil

Australia's politics has seen years of turmoil characterised by internal political feuds, with the prime minister changing five times since 2010.

Turnbull came to power last year after ousting Tony Abbott in a Liberal Party coup.

Shorten took the helm at Labor after playing key roles in two leadership coups: the overthrowing of Kevin Rudd for Julia Gillard in 2010, and the ousting of Gillard for Rudd again in 2013.

Rudd was soundly defeated by Abbott in 2013, after which Shorten took over the party.